Oklahoma produced about 476,000 barrels of oil per day and around 3.2 billion cubic feet per day of natural gas. The state remains active in drilling and completions, particularly in the STACK and SCOOP plays. Top operators are Devon Energy, Chesapeake Energy, Continental Resources, Marathon Oil, and Cimarex Energy. Major pipelines include the Keystone Pipeline, Cushing Oil Hub, Enbridge’s Flanagan South Pipeline, Oneok’s Sterling III Pipeline, and Tallgrass Energy’s Pony Express Pipeline.